package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/**
 * @author zzzhc
 * @version 1.0
 * @description: TODO
 * @date 2022/10/10 10:15
 */
@RestController
@Slf4j
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    /**
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
        // file 是一个临时文件 需要转存到指定位置 否则本次请求完成后临时文件会删除
        log.info(file.toString());

        // 原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        // 使用UUID重新生成文件名 防止文件名重复造成文件覆盖
        String fileName = UUID.randomUUID().toString() + suffix;

        //判断目录是否存在 不存在要创建
        File dir = new File(basePath);

        if (!dir.exists()) {
            //目录不存在 需要创建
            dir.mkdirs();
        }

        try {
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }

        //
        return R.success(fileName);
    }

    @GetMapping("/download")
    public void downLoad(String name, HttpServletResponse response) {
        // 输入流 通过输入流读取文件内容
        try {
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));

            // 输出流 通过输出流将文件写回浏览器 在浏览器展示图片
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, len);
                outputStream.flush();
            }

            // 关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
